CANTALOUPE
Cucumis melo L.
 

Family Characteristics  | Crop History and Development | Plant Characteristics | Propagation Methods
Cultural Practices | Insects | Diseases | Harvesting | Post Harvest

FAMILY CHARACTERISTICS
    The Cucurbitaceae contains over 90 genera and 750 species.  They are predominately warm season crops of tropical and temperate subtropical origin, many of which thrive in hot and humid conditions.  Members of this family are known as vine crops, having a prostrate or climbing nature, and are characterized by tendrils.  Most are herbaceous annuals, few are perennials, and all are frost sensitive.
    Plants in this family bear alternating leaves, which are simple and palmately lobed or palmately compound.  The flowers of this family are generally large and showy, lasting but a day.   Flowering characteristics within this family are highly variable between and within individual species.
    Fruits borne from the Cucurbitaceae family are the economic portion.  Yet in certain regions, the shoot and flowers of certain species are also utilized.  Botanically, the fruit is a pepo: the ovary wall is fused with receptacle tissue to form a hard rind. The fruits have a wide range of vegetable uses: salad (cucumbers), cooking purposes (all the gourds, pumpkin and squash), dessert fruits (watermelon, muskmelon, honeydew, and cantaloupe), and may also be candied or preserved (ash gourds, cucumbers, and watermelon rinds).  The fruits are a good source of carbohydrates, vitamin A, ascorbic acid, and minerals.
    In production, most plants are seed propagated.  Great care must be taken to maintain purity in seed production, especially within the C. pepo species because of high interfertility.  Cross-pollination will not affect the flesh quality of the resulting fruit, but rather it will be expressed in the next generation.
    Other family members include:
        Benincasa hispida L.; Uax Gourd
        Citrullus lunatus (Thung.) Mansf .; Watermelon
        Citrullus lunatus var. citroides (Bailey) Mansf.; Citron, Preserving Melon
        Cucumis anguria L.; West Indian Gherkin
        Cucumis melo L. (Chito group); Mango Melon, Garden Lemon
        Cucumis melo L. (Conomon group); Melon, Oriental Pickling Melon
        Cucumis melo L. (Flexuosus group); Armonian Cucumber, Japanese Cucumber, Uri
        Cucumis melo L. (Inodorus group); Melon, Muskmelon, Winter Melon
        Cucumis melo L. (Reticulatus group); Melon, Muskmelon, Cantaloupe
        Cucurbita maxima Dutch.; Winter Squash, Pumpkin
        Cucurbita mixta Pang.; Pumpkin
        Cucurbita moschata Poir.; Winter Squash, Pumpkin
        Cucurbita pepo L.; Winter Squash, Marrow, Summer Squash, Pumpkin
        Cucumis sativus L.; Cucumber
        Lagenaria siceraria (Mol.) Standl.; Bottle Gourd
        Luffa acutangula Roxb.; Angled Loofah
        Luffa cylindrica Roem.; Smooth Loofah
        Momordica charantia L.; Bitter Gourd, Balsam Pear
        Sechium edile S.W.; Chayote
        Telfairia spp.; Oyster Nut
        Trichosanthes anquina L.; Snake Gourd

CROP HISTORY AND DEVELOPMENT
    Overview  The species Cucumis melo var. reticulatus is native to parts of North Africa and today is referred to as "cantaloupe melon".  Cantaloupe was cultivated in Egypt as early as 2400 BC though at this time no distinction was made between netted and non-netted types and muskmelon was the name used.  Early evidence of muskmelon can be traced as spreading across the Mid-East (Iran and India) which is considered as another point of origin and diversification.  By the 1500’s Spain had brought C. melo var. reticulatus into production.   From there it crossed the Atlantic on Columbus’ second voyage, where North American Indians began to put it into production.  By the mid-1600’s, it was cultivated from Florida to New England.  Genetically, cantaloupe became highly diverse early in its production.  In 1881, W Altee Burpee Co. introduced a highly netted cultivar- ‘Netted Gem’- from which many modern muskmelons have been derived.
    In the United States, the true muskmelon is called “Cantaloupe.”  The true cantaloupe is Cucumis melo var. cantaloupensis. Cucumis melo var inodorus is another significant melon of this species.  This group is often referred to as "Winter Melon," and includes the honeydew, casaba, Crenshaw, Persian, and others.  They are white skinned with either smooth or corrugated surface.  Winter melons ripen late and have a storage life of about a month.
    In the United States cantaloupes are classified by location.  The Eastern-type cantaloupe is round to oval , usually sutured, and netted, and is not intended for long distance shipping. Many of these cultivars are disease resistant or tolerant, primarily to Fusarium wilt and/or powdery mildew.  The varieties 'Eclipse', 'Starship', and 'Cordele' have excellent quality and are sold to both local and shipping markets.  They are mid-weight fruits (4-7 lbs) with moderate to heavily netted skins.  Days to maturity for each of these varieties is 85 to 86 days.
    The Western-type cantaloupe is round to slightly oval, sutureless, very well netted, with a firm flesh that keeps well over long distance shipping.  These are generally smaller than the Eastern-type (averaging 3 to 4 lbs), maturing a bit earlier (80 days).  Their shelf life tends to be longer.  The varieties 'Super 45' and 'Laguna' are considered the best quality throughout various parts of the US (primarily the central states).  'Super 45' is tolerant to powdery mildew.  ‘Earlisweet’ is resistant to Fusarium race 1.  The high quality variety, ‘Harper Hybrid’ also has resistance to Fusarium wilt.
    There are many melon varieties in production, most of which are specialized in niche markets.  Honeydew type melons of excellent quality are the cultivars 'Passport', 'Sweet Dream', and 'Venus'.  Of these, 'Passport' has the best possibilities for limited shipping.  They each have a netted exterior and a juicy green flesh.  The varieties ‘Earlidew,’ ‘HoneyDew Green Flesh,’ ‘Tam Dew,’ and ‘HoneyDew Orange’ are in production for both shipping and local consumption.  ‘HoneyDew Green Flesh’ has disease resistance to crown blight and ‘Early Dew’ to Fusarium wilt. 
    The casaba melon has characteristically spicy flesh; the Persian melon has orange-pink, sweet  fruit.  These are two of the more popular varieties in niche markets.
Honeydew Melon
    Production  In 1996, there were 106,570 acres planted in the United States, having a value of $400,795,000 nationwide.  The primary production areas are in the western states of CA, TX, and AZ (arid and semi-arid regions).  California acreage accounts for 70% of US production.  The top melon producing states of the southern US were Georgia, with 3,865 acres in production;  Virginia, 1,020; Florida, 732; and Oklahoma, 675.  The per capita consumption of cantaloupe has been declining over the past 50 years.  In 1946, the per capita consumption was 11.2 pounds, by 1993, it had dropped to 8.5 pounds.

PLANT CHARACTERISTICS
    Overview. Cucumis melo var reticulatus is a warm season vining crop, generally requiring 80 to 120 days of warm conditions from seed to maturity.  Best melon quality is obtained in areas with high temperatures, high light, minimal rainfall, and relatively low humidity during the growing season.
    Roots   Cantaloupe roots spread out laterally and vertically to substantial depths.   As common to most Cucurbitaceae, cantaloupes have a substantial volume of fibrous roots.  As the vine begins to lengthen, root initials develop at the nodes.  These roots become more significant for nutritional and water acquisition to the growing vine and fruit.  If the vines are disrupted and the roots are broken, productivity is diminished.    In plastic culture this effect is diminished or eliminated.
    Stem The main vine grows about 18 inches without branching and produces only male flowers
(with 3 to 5 stamen).  After this, the stem branches out from the crown. Each branch of the main stem bears 1 to 2 perfect flowers near the connection to the main stem.  Under favorable conditions, these perfect flowers and those formed on the main stem just before branching form what is called the ‘crown set.’  Heavy crown set is desirable because of the early harvest and generally better market prices high fruit quality, and concentrated maturity. Stems of cantaloupes are cylindrical, and covered with trichomes.  They are rigid and brittle, not responding well to movement.
    Flower  Cantaloupe flowers are andromonoecious, first producing groups of male flowers in clusters in the lower leaf axils, then producing single perfect flowers (those having both male and female organs) along the branching stem.  Each of the flowers is open for only one day before senescing.


(diagram provided by www.acesag.auburn.edu)
    Fruit  In order for fruit set, pollination must occur.  Many growers have found adequate pollination requires the introduction of honeybees.  Ten to 15 bee visits per fruit is key for adequate seed set, thus a marketable fruit size. This  increases earliness, the yield, and the quality of the crop.
     The fruit set of cantaloupe is cyclic.  Several fruit are set per plant in each cycle.  Only one to four fruit per plant mature to marketable size as the previously set fruit inhibit the growth of younger fruit.  The reduction in fruit size and soluble solids occurs in proportion to the increased set.
    Seed Numerous cream colored seed are borne internally in a mucilage along receptacle tissue in the locular cavity.  1000 to 1,200 seeds are contained in each ounce, and have a potential viability of 5 years.
Cantaloupe seeds

PROPAGATION METHODS
    Overview.  C. melo var reticulatus is propagated by seed.  Germination of the seed occurs at moisture levels from slightly above permanent wilting to full water capacity.  The optimum temperature for germination is 73 to 74F (23-24C), yet the range is from 70 to 95F.  The use of fungicide treated seed prevents damping off which is prevalent under cool, wet, soil conditions common in the spring planting season.  Transplants are often used in field production, having various benefits.
    Direct seeding  After the danger of frost, seeds are planted along the rows at a depth of to 1 inch.  Two to 4 pounds of seed are used per acre (19,000 to 20,000 seeds per pound).
    Transplants The use of transplants has become favorable.  Seed costs are reduced using transplanting techniques over direct seeding; using 4 ounces to get the same plant stand as when using 3 lbs per acre when direct seeding.  Seeding for transplants is performed in greenhouses or hotbeds 2 to 4 weeks prior to the date of expected out planting.  Two to 3 seeds are planted in each 3 to 4 inch round or square peat pot or plug tray.  They are then out planted when they have 2 or 3 true leaves.  Transplants result in earlier production - especially when used with polyethylene mulch. Some of the benefits of using transplants are the earlier yield, the decreased cost of hybrid seed, as well as being able to take full advantage of drip irrigation and black plastic.
    Care must be taken with transplants (and young seedlings) to prevent damage from wind and sand.  Often windbreaks of grasses provide adequate protection.

CULTURAL PRACTICES
    Overview. The trend in recent years has been to use a combination of soil fumigation, black plastic mulch, and drip irrigation to produce a higher quality and earlier yielding fruit.  The use of crop rotation with a winter cover crop can increase the soil tilth and decrease pest and pathogen activity.   Crops such as winter rye should be plowed under at least 1 month before planting. Even if using crop rotation, 
melons should not follow other melons or cucurbits in the
Cantaloupe field
Cantaloupe fruit
rotation because of potential disease problems.  It is best to wait three years before planting melons on the same ground.   During the production of the melons, bees are required for adequate fruit set and size.
    Soil Considerations  The soil environment preferred by cantaloupe is a well drained, sandy loam.  Heavy clay or peat soils tend to not heat up as quickly as sandier soils, and also hold more water and invite more pathogen activity.  A soil pH between 5.5 and 7.0 encourages adequate nutrient availability and uptake.  If pH is lower than 5.5, foliage yellows and produces fewer perfect flowers and/or blossom may abscise.  Performing soil tests prior to field preparation  is essential for determining the liming requirement as well as nutrient availability in the soil, providing insight into the fertility program for that particular site.
     In making initial assessments of the land, a history of the land should be obtained and soil testing performed to determine the past chemical use and any possible residual effects (especially pesticides and herbicides).
    Temperature During germination of seed, the soil temperature should be above 60F. The optimal air temperature is 90F.   Cantaloupe performs best if the mean temperature during the growing season is 65 to 90F.  Temperatures of 110 to 115F cause vines to temporarily wilt, resulting in sunburned fruit with a reduced shelf life.
    If grown in cooler temperatures (especially those of the east and south), pathogen infestation becomes problematic.
    Planting Date In the southern states, seeds for transplants are sown in March, and seedlings are planted in the field throughout April.  In general, seed are sown or seedlings out planted 2-6 weeks after danger of last frost.
    Bed Preparation and Plant Spacing Commercial production in the South has tended to utilize raised beds, 6 to 8 inches in height, which facilitates in soil drainage.  The raised beds have 6 foot centers with 5 to 6 feet between rows.  The in row spacing of plants is 18-24 inches.  These parameters result in stands of 3,600 to 5,500 plants per acre. Traditionally 36 inches is allowed  in row. Direct seeded plants should be thinned  to 12 inches.
      The use of black plastic mulch has been beneficial in several respects.  It increases the soil temperature earlier in the growing season, conserves moisture, and reduces several common problems:  soil compacting and crusting, ground rot of fruit, fertilizer leaching, drowning of crops, evaporation, and competition from weeds.  Black plastic mulch and/or the use of transplants has been found to have greater yields, gross return, and net economic value over a conventional  practice of bare soil, direct seeded production.
    Various studies have been done using row covers in production of cantaloupe.  In the south, row covers are often not economical or even advantageous due to unpredictable spring weather conditions. If row covers are used, they offer substantial insect protection; however, they must be removed once female flowers open, or flowers will not be pollinated and fruit will not set.
    Pollinators - Honeybees  The use of honeybees is requisite for flower pollination/fruit set.  At least one beehive per acre is required, and placing up to three hives per acre will increase fruit size and earliness.  The placement of hives within the field encourages more bee pollination of the cantaloupe flowers, compared with peripheral placement.  Application of pesticides should be delayed until evening when bee activity is low to avoid killing the bees.  After fruit has been set, the hives can be removed.  Many growers opt to rent hives rather than buy and maintain them on their own.
    Fertility  Cantaloupe requires a moderate level of soil and plant fertility.  Fertilizer applications should be made at least three times:  broadcast and disked in or deep drilled; banded in place with planter; and side dressed when vines begin to run. Fertilizer can be applied preplant or through drip irrigation.  Preplant fertilizer should be applied in a 5 to 6 inch band and incorporated in the top 3 inches of the soil.  On average, the harvesting of one ton of fruit removes 4 lbs. of N, 1.4 lbs. P2O5, and 5 to 9 lbs. K2O from the soil. Considerable boron is required and may be applied as a foliar spray.  Molybdenum deficiency occurs more frequently when using black plastic and when the nitrogen fertilizer that has been applied has not been disked in deep enough, causing pH induced deficiency.  Foliar analysis of plants should be taken at least two times during the growing season.  The nutrient sufficiency ranges at the time between the initial flower start to the formation of small fruit (time 1) and between the formation of fruit to harvest (time 2).
Sufficiency Range1
Macronutrients 
 
Micronutrients
 
N
4.5-5.5%
Fe 
50-300 ppm
P
0.3-0.8%
Mn
50-250 ppm
K
4.0-5.0%
B
25-60 ppm
Ca
2.3-3.0%
Cu
7-30 ppm
Mg
.35-0.8%
Zn
 20-200  ppm
S
0.25-1.4%
Mo
No data
Sufficiency Range2
Macronutrients
 
Micronutrients
 
4.09-5.0%
Fe 
50-300 ppm
P
0.25-0.8%
Mn 
50-200 ppm
3.59-5.0%
25-60 ppm
Ca 
2.3-3.2%
Cu 
7-30 ppm
Mg 
0.35-0.8%
Zn 
20-200 ppm
0.23-1.4%
Mo 
No data
    Weed Control  As with most all crop production, weed infestation has a marked effect on crop yield.  In the south eastern United States, 13% of cantaloupe loss is attributed to weeds.  It is crucial to eliminate weed competition, especially during 3 to 6 weeks after crop emergence.  Between row cultivation and tillage techniques such as moldboard plowing, disking, and the use of plastic mulches provide adequate weed control.
    Weed competition is drastically reduced once leaves shade out the soil.  By the 6th week, leaf density has generally met this threshold, and cultivation/herbicide is no longer necessary.
    Irrigation Cantaloupes requires a supply of at least one acre inch of water per week from rainfall or irrigation in the early stages of development. Overhead irrigation during fruit development causes poor netting and a bland tasting fruit because of a low concentration of soluble solids.  In some places, low to no irrigation is recommended after early fruit set and during harvest except enough to maintain foliage so as to prevent sun scald.  Irrigation for this crop has been supplied by overhead sprinkler, furrow, and drip irrigation. Drip irrigation is becoming the acceptable method.  It has provided growers with an increased earliness and total and marketable yields compared with furrow.  In areas of limited rainfall, drip irrigation can reduce water usage by 40% less than furrow.  When used with black plastic mulch, the drip system influences reduced weed competition, no restriction of field operations due to saturated soils, and the delivery of water through the harvest season.
    Drip systems are established during bed formation, installing the drip tape 3 to 4 inches from the center of the bed at a depth of 2 to 3 inches.
    Fertigation is possible and effective with drip irrigation systems.  It is useful in condensing fertilization and irrigation scheduling.  The following table is a general recommendation for fertigation:
Total Fertigated N Requirement 
Actual N/Week (lbs./acre)
Ammonium nitrate (lbs./acre/wk)
Ammonium nitrate 
(lbs. per 1000 plants/wk)
Calcium nitrate (lbs./acre/wk) 
Calcium nitrate 
(lbs. per 1000 plants/wk)
50 lbs./acre
6 lbs. 4 oz
19
40
8
Fertility programs should be determined through soil and foliar analyses throughout the growing season.

INSECTS
    Cucumis melo is agreeable to various insect pests.  Striped cucumber beetles, spotted cucumber beetles, pickleworms, flea beetles, melon worm, aphids and mites cause much damage to crops.  They can be controlled through the use of insecticides applied at specific times through the season.  Applications should coincide with the pest life cycle and crop maturity stage.  Insecticide use should be prevented during bee pollination, and overall limited to conserve bee populations and the parasites and predators of the mentioned insect pests.  As with the use of any other chemical, the potential residual problems should be addressed before application of chemicals to the crop.
    Cucumber Beetles  The striped (3 stripes down its back) and spotted (12 black spots on its back) cucumber beetles are small (1/5  inch long) with a yellow-green background color.   They persist through the winter either through hibernation, if cold, or remain semi-active in mild winters.  The beetles feed on alternate hosts in proximal areas until the crop is planted.  They can make early attacks on crops - just after seed emergence or transplant establishment.  The larvae feed on roots and stems, causing stunting of small plants.  The adult beetles feed on the foliage and the fruit.  Plants may be stunted or killed and fruits may be cosmetically damaged, thereby reducing marketable yield. In addition to mechanically damaging the plant and fruit, beetles are also a known vector for the bacteria causing bacterial wilt.
    Control of cucumber beetles is necessary for profitability. Crop should be monitored for beetle appearance and infestation.  Foliar sprays at onset of beetle presence can adequately diminish the beetle population.
    Pickleworm  This insect is a major (and the most damaging) pest to cucurbits.  It is the larvae of a moth that migrates north each year from tropical regions.  Female moths lay their eggs on tender buds and new leaves, and sometimes new fruit. The larvae do not emerge until later in the season, developing inside the buds and blossoms.  They cause severe late season damage by burrowing into flowers and then tunnel into  and through the fruit, causing the fruit to be unmarketable. Larvae are recognized by their pale green/black spotted bodies, which become more of a coppery color as they age .
    Control of pickleworm should begin prior to planting by deep plowing, crop rotation, and early planting of crop.  Chemical applications have limited effectiveness as larvae are rarely seen.  The adult population may be chemically controlled if begun as soon as moths appear.  Pheromone lures may be useful in attracting adults, and determining the timing of chemical applications. A few pickleworm resistant varieties are available and should be used where severe problems exist.
    Aphids and mites  These insects create problems if their populations are allowed to build up, causing plant damage by removing volumes of sap and vectoring diseases.
    Various cultural practices, such as heavy nitrogen fertilization and pyrethroid insecticide use create environments susceptible to high aphid populations by increasing plant succulence and decreasing the natural predator count.
    Mites also suck sap and can, in hot and dry weather, defoliate plants.  Infestation of mites occurs along the edge of fields where favorable, dusty conditions may exist.  Mites are minuscule arthropods, and can be monitored by shaking leaves onto a sheet of white paper and watching for moving specks or by using a hand lens to inspect.  Miticide applications five days apart are effective at diminishing population. Areas of infestation should be monitored to ensure containment.
    Chemical controls  The use of insecticides should coincide with the particular insect pest needing to be controlled.  Applications are most effective when made during specific insect stages, such as upon initial infestation, before reproduction occurs and immediately after egg hatch, to mention a few. As with the use of other chemicals, alternation of insecticides decreases the possibilities of insect populations building up resistance.

DISEASES
    Disease has been a substantial cause of crop loss, be it through defoliation, rot of plant or fruit, or loss of root system.  Disease resistance has been developed into certain varieties.  Varieties with resistance against Alternaria leaf spot, crown blight, anthracnose, cucumber mosaic, scab, downy mildew, Fusarium wilt, bacterial wilt and powdery mildew exist and should be used where such diseases are present. In many varieties, the resistance is not complete, making fungicide application necessary or beneficial.  Cultural practices, such as cullage removal and crop rotation, can also reduce disease pressure.  Diseases associated with root knot nematodes (Meloidogyne sp) are also prevalent.
    Fusarium wilt is caused by Fusarium oxysporum f sp melonis.  This particular Fusarium infects only cantaloupe, crenshaw melon, and honeydew melon.  Plants may be infected during seed/seedling stage, exhibiting “damping off” at the soil line or a failure of seeds to emerge if they are attacked earlier.  This fungus enters through natural openings or injury sites, and multiplies in the vascular tissue.  This increases in severity in warm, dry weather.  In older plants, this causes the symptoms of temporary wilting (of the vine apex) during the hottest part of the day for a few days, but then results in death of the plant.  Other plant symptoms include a progressively darkening streaking of the stem’s vascular tissue near the soil line.  In moist weather, a white to pink fungal growth may develop in infected stems.
     Fusarium rot is caused by the soil borne fungus F. roseum.  Ripe fruit are most affected.  Plastic culture reduces the pressure of this disease, which may be caused by fruit contact with the soil through a point of entry caused by an insect or mechanical injury.  Infection may also occur during and after harvest if infected fruits come in contact with healthy fruits, plants or soil.  Moist environments can lead to an increased susceptibility and presence of disease.
     The fungus survives in infected plant parts and/or the soil from season to season.  It may also survive on the roots and stems of dead plants. Removal of plant material after harvest is essential for reducing inoculum, as is strategic fungicide application.
    Tan lesions of one inch in diameter may occur anywhere on the fruit.  The decay moves inward, often through all layers of tissue.  Diseased tissue is delineated from healthy, and can be easily removed.  However, such affected fruit are not marketable.
    Mosaic Viruses: Cucumber Mosaic virus (CMV), squash mosaic virus (SqMV), and watermelon mosaic virus (WMV) are the most common viruses to attack Cucumis melo.  Symptoms of these viruses are similar, though the biological characteristics (vectors and over wintering mode) differ.  Laboratory testing is necessary to determine which virus is present.
    Plants can be infected at any stage of growth.  If infected as a young seedling, the symptoms appear on the youngest set of leaves; if on older plants, the most actively growing tissue.  A mosaic pattern develops - a pattern of varying chlorotic spots of many shades of yellow to green.  The infected leaves and vine become deformed and stunted.  A witches-broom symptom may appear.  The extent of productivity loss depends on the plant’s reproductive stage at infection.  Fruit will continue to develop normally if the plant is infected midseason, while those infected early will either not set fruit at all or set poor quality and deformed fruit.
    Controlling mosaic viruses is best performed through eradication of host biennial and perennial weeds around production areas and applications of insecticides to control/prevent populations of virus vectors (aphids and cucumber beetles) from building.  Also, it is important to use only certified virus free seeds or transplants.  Roguing infected specimen can contain in-field spreading of viruses.
    Bacterial Wilt  The causal agent of bacterial wilt is Erwinia tracheiphila.  This bacteria infects most of the Cucurbitaceae family.  An infection can spread throughout the plant in a matter of a day.  It spreads from the running vines to the crown, and spreads outward through the entire plant.  The clogging of the vascular tissue by the multiplying bacteria causes plant decline and death.  Identification techniques: look for a white ooze that is squeezed out of stem tissue. 
    The cucumber beetle is the primary vector for this disease.  Control for bacterial wilt begins with beetle eradication.  If disease is noticed in the field, an insecticide should be applied and the infected plants rogued.

Bacterial wilt
(photo provided by www.acesag.auburn.edu)
    Powdery mildew Erysiphe cichoracearum is the causal agent, which infects the majority of Cucurbitaceae crops. Symptoms of this disease appear on foliage first. Infected petioles, stems, and upper surfaces of leaves have white to gray powdery growth.  The leaves become chlorotic, turn brown and papery dry.  The loss of foliage causes plant stunting, an increase in sun scalded fruit, and a reduced sugar content in the fruit. 
    Powdery mildew is most prevalent in regions with a higher temperature (80F) and relative humidity (50-90%) through the growing season.  Under favorable conditions, the disease can severely infect the entire field in a matter of a week.

Powdery mildew
    The fungus over winters on crop debris and in weeds, which makes roguing of infected plant material (and cullage) a significant method of control.  However, this does not safe guard the crop as spores can be blown long distances with wind currents.
    Many powdery mildew resistant varieties are available, and offer the best means of controlling production loss from disease.
    Other diseases

Alternaria leaf spot

Downy mildew underside of leaf

Downy mildew upper side of leaf
    Chemical controls  A variety of fungicides and bactericides are available. Residual effects must be monitored as toxicity might build up in the soil.
    Vigorous plant growth often aids in overcoming diseases - encouraging the plants to out grow the infection.  The introduction of various microorganisms is also effective at controlling specific soil borne bacteria.  Certain strains of Streptomyces sp, a soil dwelling fungus, suppress the damage caused by Alternaria and Fusarium.  It can be applied as a seed treatment, soil drench, or through drip irrigation systems in greenhouses.

HARVESTING
    Overview Harvest usually begins 68 days after planting, or 35-55 days after full bloom depending upon cultivar and environment.  The period of harvest begins when fruits reach the desired slip stage, and lasts usually one month (~27 days) with three pickings per week, until the plants cease to produce marketable fruits. The stage at which melons are picked depends upon the final market.  Those remaining on the vine the longest tend to have the greatest accumulation of sugars.
    The harvesting of melons begins in the early morning, when fruit temperatures are cooler.  Generally, the fruit harvested from the first cycle of fruit set have the highest quality. Fruit are selected for harvest according to their stage of maturity.  Those destined for shipping are picked at the slip stage when half of the stem remains intact upon removal from the vine.  These fruits are moderately ripe having 8 to 12% soluble solids, and can be left at room temperature for several days to allow them to soften and improve in aroma and flavor.  Melons destined for local markets can remain on the vine until the full slip stage, when soluble solids reach 15% and the fruit slips free of the stem. Melons sold to local markets tend to be the most flavorful as sugar content of fruit increases only while attached to the vine.
    Ripeness of fruit is determined by physical properties or with instruments.  A well developed, raised netting; smooth, rounded stem scars; and characteristic aroma are the predominant qualities of ripeness.  The percent of soluble solids can be measured in the field with a hand held refractometer.
    Melons are usually hand harvested.  Mechanization cannot be effectively employed since maturity of fruits is highly variable.   Mechanical harvesters may be used at the end of the season when vine destruction is not the limiting factor.
    Harvestable yields vary considerably.  Two thousand to 5,000 cantaloupes may be harvested per acre when grown on bare ground, while yields on plastic mulch may be as high as 6,000 to 12,000 individual fruit per acre.

POST HARVEST
    Post harvest practices determine the deliverable quality of fruit.  Precooling is necessary immediately after harvest to slow down respiration,  preventing the burning up of sugars which reduces quality and shelf life.  Precooling may be performed using cold water (hydrocooling), cold air, or ice.  The method used is based primarily on economics and shipping practices (containers).  Most often, buyers specify the method in accordance with packing and shipping requirements.
    The shelf life of cantaloupes is generally 12-16 days.  Honeydew tend to retain quality for up to one month.  The ripeness of the fruit at harvest determines the length of storability.  Cantaloupe picked at slip can be stored for up to 15 days at 36-41F and 95% relative humidity.  Those picked at full slip will keep for 5 to 14 days at 32 to 36F and 95% relative humidity.
    Most often, melons are shipped in large boxes, but marketed to the public loosely at a per melon price.

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